1. Field of the Invention
The present invention relates to cargo loading and unloading apparatus and more particularly relates to two mobile aircraft loading and unloading apparatus each adapted to operate alone to load small containers into an aircraft or to operate together to handle large containers.
2. Description of the Prior Art
Apparatus for loading cargo into and unloading cargo from an aircraft are well known in the art and such apparatus is referred to herein as an aircraft cargo loader although it will be understood that the subject aircraft loading method and apparatus performs both the loading and unloading functions.
One such prior art cargo loader is disclosed in U.S. Pat. No. 3,666,127 which issued to Guyaux on May 30, 1972 and is assigned to the assignee of the present invention. The Guyaux loader transfers relatively small containers into and out of the aircraft through a cargo opening in the side of the aircraft. The Guyaux loader is self-propelled, is driven into position adjacent the cargo opening and is then connected to the aircraft by an adapter carried on the forward end of a vertically movable bridge. A main deck or platform is disposed rearwardly of the bridge and is elevated between a low container receiving position and an elevated position wherein the forward end of the platform engages the rear edge of the bridge to move the upper surfaces of both the bridge and platform into substantially planar alignment with the cargo supporting surface of the aircraft. Scissors assemblies are provided in the Guyaux structure for guiding the bridge and platform during their vertical movement.
Very large cargo aircraft such as Boeing 747's are now available with the cargo being loaded into the aircraft by opening a tilt-up nose to expose the very long 140 foot (43 m) cargo area of the aircraft. The air cargo handling industry and its customers not only require loaders capable of transferring small containers weighing up to about 60,000 pounds (27,200 kg) and up to about 20 feet long and 8 feet wide into the aircraft; but also require an aircraft loader capable of handling 120,000 pounds (54,400 kg) in large containers that are about 40 feet long and 8 feet wide. The term "container" as used herein is known in the air cargo industry as a unit loading device (ULD), and includes both closed containers with relatively rigid bases as well as the illustrated pallets having rather flexible bases with loads of cargo secured thereto.